Malicious PDF — malware analysis report

Static analysis result for SHA-256 481ce54b7d8520e3…

MALICIOUS

PDF

87.9 KB Created: 2021-09-04 11:55:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 4470ef10a0570b87862fce9fa1062ea5 SHA-1: 15e256c3104510e1a2ef4c9ad6d0812f29687d73 SHA-256: 481ce54b7d8520e35cb88d5358df95331fafca059dfae678098651e379454e80
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, with numerous URLs pointing to compromised WordPress upload directories and disposable hosting sites, likely serving as a distribution point for further malicious content. The presence of external URIs and the nature of the links suggest an attempt to lure users to malicious sites, consistent with spearphishing tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://krisoc.ru/uplcv?utm_term=slider+revolution+manual+pdf PDF link annotation
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609c0f9bda69a---43848701431.pdfIn PDF document text
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/qprd745nu8imj5h9sksq0cnbfj/wupopatalugigosuxo.pdfIn PDF document text
    • http://abwcockeysville.com/uploads/files/jotija.pdfIn PDF document text
    • http://protok.pro/upload/files/telojusoben.pdfIn PDF document text
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/350655812712d87be73b17677f10b11a/togaxaxapibumusefek.pdfIn PDF document text
    • https://kenadong.com/contents/files/rotawutegema.pdfIn PDF document text
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/q6s8recs53dt1ojvam9ict5kmu/80693080913.pdfIn PDF document text
    • https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/4574de4725ff90ba991040c12c7dec48/fosujikulafof.pdfIn PDF document text
    • http://brukikostka.pl/uploads/page/file/34416626963.pdfIn PDF document text
    • http://caf-ljubljana.si/docs/kuvadarubav.pdfIn PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/741085811f8c126f9e1985617169c5b4/bevijaweboruruzef.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/160900c079148c---goxisasejesinoruwuzodo.pdfIn PDF document text
    • http://alpinedelhi.com/userfiles/files/6786280335.pdfIn PDF document text
    • https://farmacieitaliane.com/documenti/file/kededatolapolirufoti.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c6069d18712---zamuregimibuwironokereki.pdfIn PDF document text
    • http://domingo.hu/ckfinder/userfiles/files/fadetisa.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/0addda8ec1ce9334e87a3c6f811e3245/78426953182.pdfIn PDF document text
    • https://ekransamara.ru/files/95493520348.pdfIn PDF document text
    • https://aimara-bg.com/userfiles/file/36150288632.pdfIn PDF document text
    • http://dogoxuavanay.vn/uploads/files/falalizusen.pdfIn PDF document text
    • http://cokhiminhhien.com/media/ftp/file/dedova.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/28028262da10547434c59fb078e66e75/gaxajigutopa.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/s8f24rgecd5pm9qdbn2431maic/jinepalajimosogesebosas.pdfIn PDF document text
    • http://hanart21.com/files/userfiles/file/kojanozigadek.pdfIn PDF document text
    • https://cleaner.pl/userfiles/file/musanuratazanuze.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f13d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF13D 10732 bytes
SHA-256: 27beefdc1776f2ab16ca43dd7c37a2536b82c8725b90ec70956060d3e4e825d9
font_01_sfnt_off000109dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109DD 18708 bytes
SHA-256: 402dd450d3ecd386001ce62c431fc9c3c2d579d394bfee61bd225f7d56261348
font_02_sfnt_off000139d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139D1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1